Straight-lift pneumatic.



. No. eaaeee.

UNITED STATES 'raTENT OFFICE. A

WILLIAM E. iria-samt,'oraAT'rLaisoRo VERMONT, AssIeNoaTo asrnroaeitn eoiirANY,

OF BRAT'lLEBORO, VERMONT, A`ICORPORA'FION Olf VERMONT.'

s'raiii(nitty-Iii'FT PNEUMATIG.- 'I

l Appiication ined Novembeirza, 1am, 403,416.

To all whom 'it may concern:

13e it known that I,W,1LLIA M E. HA-siinmi', a-citizeii otgtl-ie United States, residing at ,Irattlebtiro,y in the coniity ofl lViudham and. btate v ot Vermont, have. iiirenlted certain new and usezt'ul Improvements in Straight- Lift Pneumaties, of which the following is a specification. ,v

The invention relates .to 'the lsmall bellows or piieuinaties whichare used in wind inus'ieal instruments, such as organs, for the purpose ot'pneumatieally causing mechanf ical inorenientif Such pneuinatics comprise a base and a movable board, `which are` united together vby a flexible' membrane, serving llexible walls to inclose an exi paiisible and Aeoiitractible space or Chamber between' the base and Amovable board into These pneuiiiatics frequently require to be placed Very elo-se to each other, and d-iiiieulty has arisenthrough interference between adjacent p'neiimatiesf These pneuinatics frequently a-replaced in such situation that they are called .upon to receive Speciicationof y.

1 which air may be 'admitted' and exhausted.

interior air vpressure greater than tliefeX-f -telriial air pressure, and it .tre uently happens that the' bellows oldsot the uniting membrane are blown outwardly bythe greater internal ,air-pressure so that .the folds of the iiienihraneproject beyond the marginsfotrv the base and iiioiiable',board and there interferewith the moi-*ement ot adjacent.- ilineumatiesfand prevent then proper movement. ini'en it' there isjenou'gh' space and there is no danger ot interfering with itsgn'eighbor, the outward bulging t' the fabric. prevents restoration to, proper position when the pressure is released. ln order, as tar as possible,vto overcome this ditiiculty a slightly stiffer material has been used than would otherwise be n e'eessaifyand i the folds are tightly pressed to thereby gain some. resistance tothe pressure troiii within. The fabric ot which these iiexihle walls have been 'construete'll is' usually.` a-#rubber g coatedmiill or 4thin cotton. The coating is necessarily tliin and ot interior quality, as it cannot be sutliciently drulCanizedt-o make it reliable. lt vulcanized it iiloesgnot take the fold without being baked, all of which tends to make it stittei. folds wear rapidly and soon render the piieinn'atie. leaky and unsatisfactory inwaeJ tion.4 ln spite ot all precautions, prolonged The tightly pressed "new 1 side', results,-

rat'ented June i, 1909.'

with-.e eess fofjair pressure on tliein- Y y linfa degeneration lof the. A-straightlinescofthe foldsinto out Yardly,

bulging urVeS andthe fabric becomesset in this shape, 'forming a springy butter-like (so resistance to th'e eonti.'aeted'state which renders thepneulniatie lsluggish in its operation if it operate at all.' l

The priinaryfobjeot ottliis invention is to provide a' pneumatic with the liexible also, by virtue ot'its already outwardly disposed walls,preoludes, in case the internal airrpr'essure is' greater than thelexteriial, the-possibility of blowing inside out; Henee there is' no opportunity torltailure to act,

' norfor interference withv neighboring pneu- 'matics Phe-maximum extension ot these'Av outwardly disposed walls either iiiiated -or deflated Jv is'l not ,greater tliailtliat of the edges ofthe base and movable board ot the old style pi'ieuinaticsv with equaly power.

Although the membrane walls extend oniwardly beyond the base and ino'irable board, tlie'new style Vpneumatic occupies no more spacetlianv the old stylo' lni'latioii tends riither to diminish-the.lateral'widtli Vwithout the possibility otinei-easmg it by' blowing out.

vWhen d'eiiated the upper and lower inner 'surfaces ot the flexible membrane come together. and lie fiatlyv without forming other creases than form the' four edges-ot1 the rec:- tangular4 shape, which edges project outwardly beyond the edgesoithe -base and moiable board. y w 1 y The present improvements are illustrated in lthe accompanying drawings, whereinv iii CID

Figure l, isa top View of the new pneuvmatic. Fig. .2, is a longitudinal .section-of the pneumatic-when inlated.l Fig.p3,1s a cross section of the pneumatic when inflated.

. A ,is the' movable top board; isthe base; C, is the membrane; D, is` `one of ythe small copper clips used in this case to fasten the ends of the membrane; E, is the smal chamber between the base and movable.

board.

In makingthe-new pneumatic, a piece of soft leather, preferably soft skiver goat skin, is cut into the desired length and width, and the ends are overlapped and glued together (as yshown in Fig. 3), and the whole is then .pressed flat.. The two open ends are then closed by fastening on the copper clips D, or by gluing or other suitable means. The base B, and. movable board A, are then .glued to .the bottom and top of the foldedl membrane. The membrane has holes registering with the holes E, and F.

" Thel action of the new pneumatic is in edect similar to that of those which have been in extensive use inwind musical instruments; The air on being admitted to the chamber through the aperture F, tends to fill the chamber, thereby separatingthe movable board A from the base B, and giving the-membrane C," the appearance of a pillow. The edges of the copper clips' D, as

shown, are bent outward presenting curved` bearing surfaces to prevent cutting into and injuring the'delicate material of whichthe flexible membrane is composed. The air being allowed to escape, the upper and lower interior surfaces of the membrane again come into contact witheach other as usual in thedeflated state. No internalA bellows folds prevent this complete return. The use of a very soft leather without bellows folds obviates the possibility of such a condition as in the Old .pneuinatics where stiffness, long Ause, and prolonged internal air pressure f Jcause the fabric ofthe walls to set in bulging curves offering a resistance to deliation.

As the result of this improvement membranes of the pneumatics may be made of very delicate material so asto quickly respond to-;clifl'erences in pressure, will act rapidly even on a long tube where the frictionof the tube absorbs a great deal of the effect of the air motion, and every possibility of the accident of blowing out isfobviated because the walls are already voutwardly disposed. l

The total 'area of the new pneumatic with its outwardly extending 'membrane folds is no greater than that of old pneii'inatcs of vequal power. The" drawings illirstrate thepneumatic on an enlarged scale.

I claim y l. A lstraight-lift pneumatic com osed of a base; a movable board; a tlexib e'mem- .brane uniting said base and Vmovable board,

said membrane begin a soft flexible fabric folded lia-t, its two folded edges extending beyond two opposite edges of the board and base, the two -lapped edges of the-membrane being glued together andv located vbetween the base and board, and `the two openends of the folded fabric extending beyond the other two opposite lsides of .-the base and board; andelamps .atthe open ends of the folded fabric lwhich Ecover the ends' .and make .them air-tight, said' membrane conlstituting the extensible and lcontractible lair chamber ofthe neumatic, and'` being sub-v stantially pillowlike in appearance and pref sentingno internal folds.

'A straight-lift pneumatic composed of a base; a movable board; a lexiblefabri'c uniting said base andv movableboard, said fabric being folded flat, its two'folcled edges extending beyondtwo opposite edges of the board and base, the two lapped edgesof the membrane being'located' between the base and board,` and-the'two open ends.of..the folded fabric extending; beyond the other two opposite sides of the base. and board; and means for closing the o en ends ofthe fabric making them yair-tig t, said vfabric constitutingfthe extensible and contractible .airV chamber ofthe pneumatic, and present-` ing no internal folds.

3. A straight-lift pneumatic com osed of abase; a movable board; a lexib e fabric uniting said base and movable board, said fabric being folded flat and' extending out wardly beyond all four edges of the board' and base and constituting the extensible and contractible air chamber of the pneumatiqf and presenting no .internal folds; and means for closing the open ends of ,thefa'bricmakf ing them lair-tight. In witness whereof, I have hereimto si ned my name inthe presence of two subscri ing ,4

witnesses. l l

WILLIAM E; HAsxELL.

lVitnesses: C. N. MoRAN,

L.y W2 HAWLEY. 

